Apparatus for feeding cleats to boxmaking machines



D. e. KINGSLEY 2,827,201

March 18, 1958 APPARATUS FOR FEEDING CLEATS TO BOX-MAKING MACHINES 4 Sheets-Sheet 1 Filed Sept. 20. 1954 O Q 9 O 0 O Q 0 0 G 0 ATTORNEYS.

March 18,1958 D. G. KINGSLEY APPARATUS FOR FEEDING CLEATS TO BOX-MAKING MACHINES 4 Sheets-Sheet Filed Sept. 20. 1954 ATTORNEYS.

ams xv March 18, 1958 KINGSLEY 2,827,201

APPARATUS FOR FEEDING CLEATS TO BOX-MAKING MACHINES Filed Sept. 20. 1954 4 Sheets-Sheet 3 lllllll mm 1 VEN 0R 1 9 David G. K ngs ey M, mm W74 ATTORNEYS.

'March 18, 1958 D16. KiNGSLEY APPARATUS FOR FEEDING CLEATS TO BOX-MAKING MACHINES Filed Sept. 20. 1954 4 Sh 02 10 wa a; x

BY JJQ l4 (1 4, mm N ATTORM; Y5.

Unite APPARATUS FQR FEEDING CLEATS TO BOX- MAKING MACHINES Application September Ztl, 1954, Serial No. 457,066

2 Claims. (Cl. 221-116) This invention relates to apparatus for dispensing cleats to wirebound box-making machines of the type disclosed in United States Patent No. 2,304,510, issued December 8, 1942.

In such machines, properly assembled cleats and side material or slats are conveyed beneath a transverse bank of stapling units by which staples are driven over longitudinally extending binding wires, through the side material or slats and into the cleats to form wirebound box blanks. Each of these box blanks comprises a plurality, usually four, box sections or sides which are foldably secured together by the binding wires. The cleats are frequently provided with mitered ends which fit snugly together when the box blanks are folded around to set up the box. Where the box has oblong ends, two lengths of cleats are required, with alternate sections of the box blanks having cleats of different length.

The cleats and side material or slats are conveyed through the box-making machine by continuously moving conveyor bands which carry adjustably positioned projecting push elements which engage the cleats and side material or slats and maintain their properly assembled relationship.

In United States Patent No. 2,658,631, issued November 10, 1953, there is disclosed apparatus for mechanically dispensing cleats into proper position in the spaces ahead of the push elements on the conveyor bands of a wirebound box-making machine. This apparatus eliminates some of the manual labor which has previously been required in the laying of cleats and thereby enables a substantial reduction in the cost of producing wirebound boxes and crates.

The present invention is in the nature of an improvement over the invention of said Patent No. 2,658,631, to the end of achieving a more dependable supply of cleats to the conveyor bands of wirebound box-making machines. The invention allows greater flexibility in positioning of the cleat dispensing units when cleats of two different lengths are being fed. The invention provides means for feeding rnitered cleats whose length exceeds specified tolerances, as well as means to facilitate the movement of cleats supplied from the first of two cleat dispensing units, beneath the column of cleats contained within the hopper portion of the second cleat dispensing unit. The invention also'provides a dual safety gate having one member which opens to permit egress of two adhering cleats, thus clearing a slight cleat jam without interrupting production of the boxmaking machine while its other member opens only in the event of a serious cleat jam or other malfunction and the opening of this second member stops the conrates Patent ii elements involved.

In the drawings:

Figure 1 is an elevational view of the outer face of a cleat dispensing apparatus embodying features of the present invention.

Figure 2 is a top plan view of the apparatus shown in Figure 1.

Figure 3 is an end elevation of the cleat dispensing apparatus as viewed from the end which appears at the left in Figure 1.

Figure 4 is a fragmentary side elevational view of the inner face of the cleat dispensing apparatus, showing particularly its output end.

Figure 5 is an enlarged fragmentary view of the lower portion of the cleat dispensing apparatus.

Figure 6 is a top plan view of the portion of the apparatus shown in Figure 5.

Figure 7 is a vertical sectional view taken on line 77 of Figure 6.

Figure 8 is a fragmentary elevational view of the lower portion of an alternative type of cleat dispensing apparatus embodying features of the present invention, said apparatus being of the gravity feed type and including means for displacing the bottom cleat to permit a cleat pushing element to enter and continue freely beneath it.

Figure 9 is a view similar to Figure 8 except that the cleat displacing mechanism is shown in operative position, with the bottom cleat raised above its normal position.

Figure 10 is a top plan view of the portion of the apparatus shown in Figure 9.

Figure 11 is an end view of the apparatus looking toward the end which appears at the right in Figure 9.

Figure 12 is a view of the lower portion of a gravity feed-type cleat dispensing device embodying features of the present invention including, at its output end, a dual member safety gate and, at its opposite end, means for positioning tilted cleats.

Figure 13 is a view similar to Figure 12 except that the members of the safety gate and the elements for positioning tilted cleats are shown in operative position.

Figure 14 is an elevational view of the end of the apparatus which appears at the right in Figure 12.

Figure 15 is a vertical sectional view taken on line 1515 of Figure 12.

The cleat dispensing apparatus of Figures 1-8 is adapted to be supported, as is particularly shown in Figure 3, by one of the pair of longitudinally extending side rails which form part of conventional wireboun box-making machines. One of said side rails is positioned at each side of the machine to support the conveyor bands. While each of the side rails bears cleat dispensing apparatus, it is deemed sufiicient to illustrate and describe only one of the dispensing units, since they are identical except for reversal of parts.

As may be seen in Figure 3, each of the side rails is built up from a pair of angle members A and B which are bolted together in spaced relationship. To the upper surface of outer angle member B the cleat dispensing unit is detachably mounted at a convenient point adjacent the input end of the machine while the inner angle member A supports the conveyor bands C with its attached cleat pushing members V. The construction of said unit is generally similar to that of the cleat dispensing unit disclosed in the aforementioned Patent No. 2,658,631. Briefly, it comprises end walls D and E (Figure 2) spaced I secured. To the outer face of an upstanding flange 12 of support plate10 is mounted a solenoid 14 which, as shown more clearly in Figures 2 and 6, has an elongated rod member 18 pivotally connected to its armature 16.

Pivotally mounted on a stud 20 (Figure 2) projecting from the upper surface of support plate 11 (Figure 2) is an irregularly shaped finger 22 having an outwardly projecting arm- 24 which is pivotally connected to the free end of-the aforementioned rod member 18. The finger 22 is slidably supported on the aligned upper surfaces ofsupport plate 10 and the base member H of the dispensing unit.

As shown particularly in Figure 3, this base member H is supported on the upper surface of outer angle member B and has at its inner face adjacent conveyor band C a vertical flange I which serves as-a stop for the cleats ejected from the cleat dispensing unit and also as a guide forthe cleats as they are moved by the cleat pushing elements V.

As shown in Figures 2 and 6,-the energization of V solenoid 14 retracts its armature 16 in the direction indicated by arrow K andtcauses irregularly shaped fingers 22 to assume the position shown by broken lines L, while the deenergization of solenoid 14 permits the finger-22 to be returned to its initial position against a stop block 26 by a tension spring 28, one end of which is hooked to a stud 30 'thr'eaded'into the undersurface of rod member 18 and the other end of which is hooked to the upstanding portion of. an L-shaped stud 32 threaded into the outer face of support plate 10.

It will be seen, with further reference to'Figures 2 and 6; that the upstanding flange 12 of support plate 10 has -fastened to its inner face'a plate 34' which serves as one end wall of the cleat hopper. Longitudinal adjustment of the end Wall'34, according tothe length of the cleats being dispensed; is obtained by clamping leg 8 of support plate 10 at a suitable location along bracket 2 by means of clamping member 6.

As may be seen by reference to Figures l, 2, 3 and 4, the ejected cleat is prevented from jumping by hold-down members 36 and 38. As shown in Figures 3 and 4, hold-down member 38 is yieldingly attached to a safety gate 40 which is-hinged' at 42 to end Wall E of the hopper. An arm 44 projecting rigidly outward'from the upper end of safety gate 40 is arranged to actuate an electric switch 46; as shown by broken lines M in Figure 4, to' stop the box parts conveying mechanism in the event of a serious jam of cleats at their point of 1 egress from the cleat dispensing unit. Safety gate 40 is returned to and yieldingly maintained in its initial position by a tension spring 48 the upper end of which is fastened totarm 44 and the lower end of which is fastened to end wall E.

In'Figures 2, and 6 is shown a mechanism'which 'will-directpcleats that are within tolerances for their ,SPBCifiCd length, into proper position between the cleat pushing elements V on the moving conveyor bands, C.

This mechanism includes a gate member 50 pivotally .4 for guiding the cleats. The gate member is urged in a clockwise direction as viewed in Figures Z'and 6, by a coil spring 58 which is tensioned between the hub portion of gate member 59 and the inner face of end wall E, but its movement in this direction is limited by a stop pin 56.

The gate member 50 cooperates with a ramp block 60 to align cleats of excessive length for continuous movement. The ramp block 60 is secured on the upper surface of base member H adjacent the free end of gate member 50 and is provided with an upwardly inclined bevel 62 at its end facing toward the oncoming cleats. This bevel 62 raises the leading end of'a' mitered cleat which is too long to "enter freely into the spaces between? adjacent cleat pushing members V, thereby permittingtthespring loaded gate member 50 to swing the leading end of the cleat into proper alignment when it has been elevated to such extent that the miter will permit it to 'move' into the space between the cleat pushing members. T

It will be seen with further reference to Figures 2 and 6 that the beveled portion of the free end of gate member 50 overlies the outwardly, flaredfree end of the elongated guide 64.1 The elongatedtguide 64 is pivotally mounted on a stud 66 threaded into the vupper-surface of base member H and is urged in a counterclockwise direction as viewed in Figures '2 and 6 by a tension spring 70 {Figure 2) which has one of its endsfastened to the hub portion 72 of the guide 64 and its other end hooked about a stud 74 projecting from: the upper sur- 7 face of base 'member H, with its movement'in such direction being limited by'an adjustable stop screw 68 engaging a---flattened surface on 'the hub portion 72.

Any yielding movement of gate member 50 will thus be imparted to elongated guide 64, as indicated for example by broken-lines P intFigure 6.

The operation of thismechanism is as follows: The cleat hopper is filledwith a stack of cleats which are supported upon base member H with the bottom cleat in the arcuate path of finger 22 which is actuated by the energization of solenoid 14. This action is j initiated by each of a series of trip members R which are adjustably clamped'to-conveyor band C, each a predetermined distanceahead of one of the'cleat bers V.

As; may be seen in Figure 2, as each cleat pushing pushing mem- V memberarrives at a point adjacent the trailing'end of the bottom cleat 78 in the stack, one of the trip members R contacts a pivotallymounted'spring loaded finger 1 Strand causes it to actuate an electric switch 82 which is mounted r'adjacent the path of the conveyor band C on an=adjustable -bracket84--secured to the side of angle member A-(see also Figure 7); The actuation of electric switch 82 energizes solenoid 14, retracting its-arma- .ture ifi-and thezrod member 18'pivotally attached thereto in the direction'indicated by the arrow K. Thistaction rotates-;finger=- 22 -counterclockwise to its position shown in broken lines in Figures 2- and 6,- and the finger-pushes :the:trailing end of the "bottom cleat 78 outwardly into contact withvertical flange I and in the path of the outmumalength; r If the bottom cleat 78 does not exceed this length, itwill be directed-into the space between the push fins by--contact of its-leading end with the'obliquely positioned gate-member 50,- as shown by broken, lines 78a'and78b in Figure 2. As may bejseen iniFigures 5 and 6, in the event that 'the l ength ofecleat 78Vexceeds this tolerance, itsleading -end-cannotrnoveinto'position in, this fasion, but, as shown byrbroken ;l ines:78c, will engage: the outer end of .theprecedihgfifi ,U :and, as it moves further along,will

force outwardly the spring loaded gate'member 50 and the spring loaded guide 64, as shown by broken lines 50a and 64a. At the same time, the leading end of the cleat will climb up the bevel 62 of ramp block 60, as shown by broken lines 78d. As will be understood, the raising of the mitered end of cleat 78 produces the effect of foreshortening the length of the cleat and allows the spring loaded gate member 50 and elongated guide 64 to press the leading endof the cleat into proper alignment, with any excess in length of the cleat merely causing the mitered surface at the leading end of cleat 78 to rest upon the top of push fin U, as shown by full lines 782 in Figures 5 and 6.

When a cleat being moved as described above is too long even to be handled in this fashion, or if for any other reason the cleat does not move into proper alignment in the space between the push fins U, the elongated guide 64 will be forced to move to an extreme outer position as indicated by broken lines 641) in Figure 2, at which it actuates an electric switch 76 to stop the conveyor bands until the defective cleat may be removed, thus preventing possible damage to the apparatus.

Shown in Figures 8, 9, and 11 is an alternative construction of cleat dispensing device which, like the apparatus of Figures 1-7, is particularly useful in combination with another dispensing apparatus, for example an apparatus of the type illustrated in Figures 12-15, to supply two difierent lengths of cleats to the conveyor bands of the box-making machine, where required by the design of the box being made. In such a combination, the apparatus of Figures 1-7 or 8-11 is used to supply cleats of one length to alternate cleat spaces on the conveyor bands and the device of Figures 12-15 is used to supply cleats of another length to the remaining spaces.

The device of Figures 8-11 is of the gravity-feed type having a hopper for supporting a generally vertical stack of cleats, with a mechanism for raising the stack of cleats suhiciently to permit the oncoming cleat pushing member to move beneath the bottom cleat of the stack to a predetermined point whereupon the elevating means are retracted to allow the stack of cleats to be supported on the push fin of this cleat pushing member, thus causing the push fin to move beneath the hopper without coming into contact with the trailing end of the bottom cleat.

As shown in Figures 8, 9 and 11, this cleat displacing mechanism includes a solenoid 86 suitably mounted on the horizontal shelf portion of a U-shaped hanger member 90 fastened to blocks 92 extending between the vertical flanges of angle members A and B. The armature 83 of solenoid 86 is provided with an enlarged head which projects through an opening 94 in the base member H. When the armature is in its retracted position, as shown in Figure 8, its outer surface is aligned with the upper surface of the base member H.

As may be seen in Figures 10 and 11, the conveyor band C, which moves in the direction indicated by the arrows W, carries cleat spacing members X and Y which are clamped thereon at positions adjustable longitudinally of the conveyor band. Cleat spacing member Y is provided at its outer endwith a projecting push fin Y1, while its inner end bears a suitably shaped lug Y 2 which, as shown in Figures 10 and 11, is adapted to depress the spring loaded plungers 96 and 101) of a pair of electric switches 98 and 102 which are mounted at spaced positions alon side the path of the conveyor band.

The actuation of switch 98 energizes solenoid 86 through a conventional relay (not shown) and this, as illustrated in Figure 9, causes the armature 82", of solenoid 86 to be projected upwardly against the bottom cleat of the stack and raise the stack sufiiciently to remove the bottom cleat from the path of push fin Y1. Solenoid 86 continues to be energized by the relay so that its armature 88 remains elevated to support the stack of cleats until lug Y2 of cleat spacing member Y contacts the plunger 16%) of the second electric switch 102. The actuation of switch 102 releases the relay and deenergizes solenoid 6 86, retracting its armature 88 and allowing the stack of cleats to drop so that the trailing edge of the bottom cleat will be in the path of the push fin of the next oncoming cleat spacing member.

In Figures 12, 13, 14 and 15 is shown an alternative construction of gravity-feed cleat dispensing apparatus also embodying features of the present invention. This mechanism may be used in combination with either the apparatus of Figures 1-7 or that of Figures 8-11 to dispense cleats of a difierent size into the remaining cleat spaces on the conveyer bands. The apparatus of Figures 12-15 includes mechanism for correctly positioning any cleats which are tilted so that their leading ends rest atop the push fin of one of the cleat spacing members. As may be seen in Figures 12 and 13, this mechanism includes an angular-shaped presser foot 104 pivotally mounted at its upper end on the outwardly projecting end of a bar 106. The opposite end of this bar 106 is pivotally attached at 107 to an inverted L-shaped bracket 108 (Figure 15) which is adjustably secured to the cross brace 110 of the cleat dispensing device by a clamp member 112. The horizontal lower portion of the angular-shaped presser foot 104 is urged downwardly by a compression spring 114 interposed between it and the underside of bar 106 and guided on studs 116. The overhanging portion of the inverted L-shaped bracket 108 supports therein two spaced adjustable screws 118 and 120. The screw 118, which is positioned directly above compression spring 114, extends downwardly into the upper end of a comp-ression spring 122 which is interposed between the overhanging portion of bracket 108 and the aforementioned bar 106, yielding to allow the free end of bar 106 to move upward when necessary. The bar 106 is normally held in a horizontal position against the force of spring 122 by the screw which engages the upper surface of the bar 106 on the opposite side of its pivot 107 from the spring 122.

As is shown in Figure 13 by broken lines 124, a cleat in tilted position with its leading end at such height as to engage the undersurface of presser foot 104 is subjected to a frictional drag, tending to retard its forward movement in the direction indicated by the arrow X and cause it to drop into proper position as shown by full lines 126.

This embodiment of the invention is provided with an alternative type of means for supplying into proper spaces on the moving conveyor bands, cleats of two different lengths where required by the design of the box being made. As may be seen in Figure 12, there is mounted on the base member H, in the path of cleat movement, a cleat step member 128 which is adjustable longitudinally of the base member. The end of the step member 128 facing in the direction of the oncoming cleats is formed with an upwardly inclined bevel 130, which is positioned a short distance forward of the trailing end of the bottom cleat 132 in the hopper. As shown by full lines in Figures 12 and 13, the bottom cleat 132 is about to be moved out of the hopper in the direction indicated by the arrow X by push fin 134 of a cleat spacing member, followed by the cleat 136 from another cleat dispensing device located ahead of the device in the direction of movement of the conveyor bands.

The outgoing cleat 132 rests upon the step member 128 and supports the next-to-bottom cleat 140 and the other cleats above it in the stack. The position of the end of the step member 128 is such that the leading end of the cleat 136 from the first cleat dispensing device does not reach the step member until after it has passed beneath the trailing end of the next-to-bottom cleat in the stack. This allows the cleat 136 to pass freely beneath the cleat 140 without engaging its trailing end. When the leading end of the cleat 136 does reach the step member 123, it climbs up its beveled end 130, as illustrated in broken lines in Figure 12, in position to support the stack of cleats as the preceding cleat 132 moves the trailing end of the next to-bottom cleat 140, the cleat 136-wi l1 have dropped to a horizontal position on the step member 128 (in the same position as is occupied by the 'cleat.1;32 in Figure 13) with the trailingend of the cleat136 above the top of the push fin 138 so that the push fin 138 cannot engage the trailing end of the nextto-bottom cleat 149. The cleat 140 will thus remain in the hopper until the arrival of its proper cleat space between the push elements on the conveyor bands,

'A lso shown in Figures 12 and 13 is a dual safety gate whichembodies features of: this invention, and which functions to clear minor cleat jams and to prevent damage ofjhe; apparatus as a result of more serious cleat jams. Generally, this gate mechanism comprises two gate members which may be moved'independently of each other 'in; a counterclockwise direction as viewed in Figures 12 and 13. The outer gate 142 is, pivotally mounted at its upper ,end on a stud 144- threaded into. one flange 146 of an upstanding angle ,148 and ,is supported, in a plate 150, attached to a bracket 152 extendingsoutwardly from flange 146.

Gate-142 is normally in vertical position, as illustrated in Figure 12, and extends downwardly to such a point as to permit unrestricted passage beneath it of individual, normally positioned cleats. The upper portion of the left-hand side of gate 142, as viewed in Figures 12 and 13, is cut away to provide a notch 154 of suitable depth to receive therein the lower portion of the end wall member 156 of the cleat dispensing device, thereby establishing a continuous guiding surface, for the ends of the cleats as they move downwardly in the hopper and providing a positioning stop for gate 142.

As may be seen with reference to Figure 12, from the right-hand side of and adjacent the pivotal end of gate 142 there projects upwardly at an oblique angle an arm 158 having at its upper end a mallet-shaped head 160 (see Figure 14) which serves as a weight.

The weight'lfifi urges the gate 142 in a clockwise direction, as viewed in Figures 12 and 13, to its normal closing position in which it is shown in Figure 12. The angle of the arm 158 is such thatthe force imposed on the gate 142 by the weight 160 istat its maximum when the gate is in closed position and decreases as the. gate is opened in a counterclockwise direction as illustrated in Figure liia The gate 142, once opened, thus imposes little dragon the cleats passing beneath it.

The effect of the weight 160 in keeping the gate 142 closed is augmented by the force of alight tension spring 162 which extends between a stud 180 at the upper end of the arm 153 and another stud 182 projecting from the lower portion of the plate 150.

In its normal, closed position, as shown in full lines in Figure 12, the gate 42 prevents movement from the hopper of all but the bottom cleat. The gate 142 may be swungop en against the resistance of the weight 160 and spring 1 62'to permit an improperly positioned cleat to pass out of thehopper, or to permit the two bottom cleats in the hopper'to pass out or" the hopper simultaneously,

as illustrated in Figure 13, where these two cleats are adhering to each other, for example due to roughness of their interfaces. The opening of gate 142 thus prevents possible damage to the apparatus while avoiding the necessity of stopping the conveyor bands to clear up minor malfunctions which can be corrected merely by manually repositioning a misplaced cleat or removing a surplus cleat;

As'may be seen particularly in Figure 14, the upper gate 164 is positioned adjacent the inner-face of gate 142 with suitable clearance provided therebetween to permit each gate to move independently of the other. Gate 164 is also pivotally mounted on stud 144, and is providedwith an integral arm 166 projecting horizontally outward; In the rear face of arm 166 there is threaded aheadedscrew168which has hooked on it theuppler end of a comparatively stilf tension spring 170 whose other end 'isanchored to a stud 1 72 threaded into the upper surface of anglemernber B. 7

An electric switch 174 attached to upstanding angle member 148 is arranged to be actuated by arm' 1 66 in the event of a serious jam ofcleats. As indicated by broken lines 176 in Figure 12, the inner face of the lower portion of gate 164 adjacent the ends of the'cleats in the stack is inclined downwardly and outwardly to prevent the leading ends of cleats which, for one reason or another, have been tilted upwardly fromlclimbing the inner face of gate 164, as they are urged to do by frictional contact with lower cleats which are moving out of the hopper.

However, should the leading ends of the cleats become tilted downwardly, there is danger of aserious jam of cleats, as indicated by the fragmentary portion, of cleat 173 shown in broken lines in Figure 13. When such a jam of cleats occurs, gate 164 and its "am 166 will be caused to move in a counterclockwise direction, actuating switch 174 and causing the conveyor. bands to stop, preventing damage to the apparatus and permitting manual clearing of the cleats involved.

It will be seen that the apparatus disclosedis capable of reliably dispensing cleats into their proper'respective' positions on the continuously moving conveyor bands of a box-making machine, such apparatus being relativelyv ciated that the aforementioned and other desirable objec-' tives have been achieved. However, it should be emphasized that the embodiments of'the invention shown and described herein are intended as merely illustrative and not as restrictive of the. invention.

I claim: t

1. Apparatus for dispensing cleats, of two, difierent lengths into proper respective spaces betweenpush elements secured to the moving conveyor bands of a. boxmaking machine, said apparatus comprising'a pair of' hoppers spaced apart longitudinally of said conveyor bands, the first of said hoppers being, adapted to support a stack of cleats of one length and the second of said hoppers being adapted to support a stack of cleats. of another length, said first hopper having a movable'cleat feeding element positioned to engage the bottom cleat in the stack therein,tmotive,means for driving said cleat feeding element, actuating elements positioned on said conveyor bands in predetermined spacedtrelation to the push elements at the trailing ends, of selected spaces on said conveyor bands, said actuating elements being arranged to actuate said motive means for drivingsaid cleat feeding elements to eject cleats .into said selected spaces, said second hopper. being. arranged to support the stack of cleats therein in a, generally'vertical column with the bottom cleat in said column .in the path of said push elements whereby said cleats will drop individually and successively into the remainingspac'es on said conveyor bands.

2. In apparatus for dispensing, cleats of two diflferent lengths into alternate spaces between the push elements secured to the moving conveyor bands of a box-mailing machine, said apparatus being of the type including two cleat hoppers spaced longitudinally of said conveyor bands, the first of said hoppers dispensing cleats of one of said lengths into alternate'spaces and the second of said hoppers dispensing cleats of the otherrlength into the remaining spaces, with a cleat supporting surface for supporting said cleats as they are transported through said machine by said push elements, the combination of a cleat elevating step arranged to raise said cleatsabove said cleat supporting surface, the end of said cleat elevating step which faces in the direction of the oncoming stack of cleats in said second hopper, whereby the cleats from said first hopper will enter said second hopper at a level low enough to clear the trailing end of the next-to-bottom cleat in said second hopper.

References Cited in the file of this patent UNITED STATES PATENTS 740,202 Sweeney Sept. 29, 1903 10 Briggs Dec. 26, 1905 Stewart May 14, 1907 Newdick Apr. 19, 1921 Koehler Feb. 3, 1925 Willard Oct. 23, 1928 Bronson et a1. Dec. 16, 1930 Raetsch Aug. 17, 1943 Heinrich July 15, 1952 Shannon et al May 26, 1953 

